Vehicles, computers and other similar devices include a plurality of cooperating components. For example, an automobile includes body panels, an engine, various electronic modules, etc., that collectively define the automobile. Unfortunately these components may be stolen and resold individually for use in another vehicle. The entire vehicle may also be stolen, but the parts sold separately to avoid discovery. The value of the automobile components sold individually may be greater that the value of the assembled automobile. Similarly, a computer may have valuable components, such as a processor, plug-in memory module, display, etc. that may be stolen, while leaving the rest of the computer in place. Components that have a high value-to-weight or value-to-size ratio are common targets for thieves.
One approach for discouraging resale of component parts provides a unique marking on the component. For example, a serial number or other identification number may be permanently affixed to the component, such as an engine block or body panel. Unfortunately, such markings can be removed or the part sold to an unscrupulous buyer who has no concern for the authenticity of the component or the legal owner of the component. Irrespective of the markings on a conventional component, an automobile or computer, for example, will still function even with a stolen part or component installed therein.
Other approaches have been disclosed for discouraging the theft of components, or discouraging theft of the entire device where the stolen device is likely to be later sold as individual components. For example, U.S. Pat. No. 5,349,326 to Yamada discloses a car audio device including a main body and a front panel detachably mounted to the body. The car audio device will not operate unless a controller matches a code from the detachable panel to a code stored in memory in the main body portion. The secret code can be changed to any desired code by the owner via controls carried on the front panel. The secret code may also be generated and stored at the factory. Accordingly, the front panel and body portion may not be stolen and used separately.
Along these lines, U.S. Pat. No. 4,494,114 to Kaish discloses a lock-out security technique for microprocessor controlled electronic equipment. In particular, upon the occurrence of a disabling event, such as the removal of the equipment from its normal installation, and/or disconnecting of electrical power, the equipment will remain disabled until a code is manually entered via a keyboard. A publicly known code is installed at the factory and thereafter, the user installs his own private code. A secure factory initialization code may be used to allow for storage of the public code.
U.S. Pat. No. 5,229,648 to Sues et al. discloses a security system for a vehicle and includes a central processing unit that communicates with various components of the vehicle. If the codes returned from the components are incorrect, out of sequence, or missing, the processor will disable the components. An international database is used to approve any component changes within a vehicle. The database does not permit a part to be added to the active vehicle parts list unless a similar part is taken from a factory/dealer replacement parts list. Roadside service of a vehicle can be accommodated by using a portable computer and cellular telephone link to reprogram the processor to accept replacement parts. Encryption reduces the possibility of compromising the security of transmitted messages. Unfortunately, the tasks of maintaining such a comprehensive database and further ensuring its security may make this approach difficult to implement on a large scale.
U.S. Pat. No. 5,006,843 to Hauer discloses a security system for motor vehicles which includes an integrated circuit mounted inside vital accessories and which prevents these accessories from operating without the entry of a proper code by a user. In a maintenance state, a specific stored code word enables the starter permanently and no external code word is required for starting. This maintenance mode is used for delivery of a new vehicle, for service of the car and for replacement. The maintenance mode is ended by the user entering the code word of his choice.
Suggested improvements have been made in the area of security for devices and equipment such as vehicles and computers, which include cooperating components. Unfortunately, there may be substantial shortcomings associated even with these suggested improvements. For example, the management of a central database for all of the parts of all automobiles may be impractical. In addition, those systems requiring the user to remember a unique code or password for extended periods may also be impractical.